The invention relates to a fuel injector for internal combustion engines, of the kind which can be used for injecting fuel under high pressure into the combustion chamber of an internal combustion engine.
A fuel injection nozzle or fuel injector for internal combustion engines is known from German Laid-Open Application DE 29 20 100 A1. In the known fuel injector, a nozzle needle is arranged in a longitudinally movable manner in an injector body and interacts by means of a sealing edge formed on the nozzle needle with a nozzle needle seat formed on the injector body and opens and closes a plurality of first injection openings by means of its longitudinal movement. Adjoining this at the combustion-chamber end, the nozzle needle has a pin region, which projects into a blind hole formed in the injector body and thereby closes a plurality of second injection openings. Up to a partial stroke of the nozzle needle, fuel flows into the combustion chamber of the internal combustion engine only through the first injection openings, while the pin region seals off the second injection openings. After the partial stroke, the pin region emerges from the blind hole and thus exposes the second injection openings. A step-shaped injection characteristic which includes good suitability for very small quantities can thereby be achieved. However, the sealing function of the pin region when projecting into the blind hole requires high accuracy of manufacture and high wear resistance.